Poly(amide-ether-imide)s

ABSTRACT

Disclosed is a poly(amide-ether-imide) and the preparation of the same. An ether chain-containing aromatic diamine is subject to thermal condensation with trimellitic anhydride (TMA) in a polar solvent to obtain diimide dicarboxylic acid, followed by polycondensing the diimide dicarboxlic acid with diamine to form the poly(amide-ether-imide). The poly(amide-ether-imide) of the present invention has superior strength, heat resistance, and processability. The preparation of the present invention is simple and economic.

This application is a divisional application of application Ser. No.08/044,237, filed on Apr. 7, 1993, now U.S. Pat. No. 5,268,487.

BACKGROUND OF THE INVENTION

The present invention relates to a poly(amide-ether-imide) and thepreparation of the same, and in particular relates to apoly(amide-ether-imide) prepared by subjecting a cyclizedimide-containing dicarboxylic acid to polycondensation with an aromaticdiamine.

Poly(amide-imide)s are characterised as high performance polymericmaterials having both superior heat resistance of polyimide and superiortoughness, and processability of polyamide. The most economic and simplemethod for the preparation Of poly(amide-imide) is by the use oftrimellitic anhydride (TMA). TMA has the characteristics of bothanhydride and carboxylic acid, hence when it is subjected topolycondensation with diamines, poly(amide-imide)s are formed. However,difficulties are encountered when it is desired to prepare linearpoly(amideimide)s with high molecular weight from TMA and diamine. Ingeneral, poly(amide-imide)s are prepared by first activating TMA to4-chloroformyl phthalic anhydride, then subjecting the anhydride to lowtemperature solution polycondensation with diamine to formpoly(amide-amic acid), and followed by cyclizing the amic acid by thefilm-baking method or high temperature ring-closing method, or theaddition of condensing agents, such as acetic acid anhydride. However,there are several problems with the above-mentioned method, which aredescribed as follows.

(1) Activation of TMA increases the manufacturing cost and the operationprocedures. The activated TMA is unstable and is easily hydrated anddegraded.

(2) As the polyamide-amic acid prepared by low temperaturepolycondensation contains strong acid (HCl), the amide bonds of the amicacid will break when subsequently subjected to cyclization by directbaking or by the addition of solvents at an elevated temperature. Thisbreakage of amide bonds will cause the reduction of the molecular weightof the resultant products.

(3) The manufacturing cost will also increase if a treatment with aceticacid anhydride is used.

To overcome the above problems, U.S. Pat. Nos. 3,920,612 and 4,048,144disclose a process comprising first subjecting TMA to polycondensationwith amine to form diacid of imide, then activatiing the diacid to acidchloride, and followed by polycondensing the acid chloride at lowtemperature. However, high manufacturing cost is still a problem and theintermediate acid chloride is not easily purified.

Japan laid-open Patents Nos. Sho 44-19274, Sho 46-20068 and Sho 50-33120describe a process for preparing a poly(amide-imide). The processincludes reacting diisocyanates with TMA or its derivates in specificsolvents and catalysts at an elevated temperature. As the source ofdiisocyanates is limited and the diisocyanates are not as stable asdiamine in storage, this process is not satisfactory.

Japan laid-open Patent Nos. Sho 49-4077, Sho 58-180532 and BritishPatent No. 1383480 describe a poly(amide-imide) prepared by directcopolymerizing TMA and diamine in the presence of catalysts at atemperature of 200° C. However, at such a temperaure, the polymer iseasily coloured and a linear polymer is not necessarily formed.

Accordingly, a novel synthetic method of poly(amideimide) was developedby the inventors in 1989, which method comprises first preparing animide-containing dicarboxylic acid by thermocondensation, and thensubjecting the acid to polycondensation with diamine directly by using aphosphite condensing agent. The manufacturing cost of this method is lowand high molecular weight polymers are obtainable.

SUMMARY OF THE INVENTION

It is therefore an object of the present invention to provide apoly(amide-ether-imide) with superior heat resistance, strength, andprocessibility.

Another object of the present invention is to provide a economic andsimple method for the preparation of poly(amide-ether-imide).

DETAILED DESCRIPTION OF THE INVENTION

In order to attain the above objects, the present invention uses etherchain-containing aromatic diamines as raw material in the preparation ofpoly(amide-ether-imide)s. Specifically, the process of the presentinvention comprises subjecting an ether chain-containing aromaticdiamine to thermocondensation with TMA in a polar solvent to formdiimide dicarboxylic acid, followed by polycondensing the diimidedicarboxylic acid with diamine.

Suitable ether chain-containing aromatic diamines used in the presentinvention are derivative of bisphenol, which has the following formula:##STR1## wherein R₁ represents ##STR2##

These ether chain-containing aromatic diamines are prepared bythermocondensing various bisphenols with 4-chloronitrobenzenes orthermocondensing dihalides with 4-aminophenols in a polar solvent ofinorganic base, followed by a hydrogenated reduction. The bisphenolused, for example, can be any one of the following: hydroquinone,resorcinol, catechol, methylhydroquinone, 4-chlororesorcinol,4,4'-biphenol, 3,3'-dimethyl-4,4'biphenol, 3,3',5,5'-tetramethyl-4,4'-biphenol, 4,4'-dihydroxyphenyl ether,4,4'-dihydroxyphenyl sulfide, 4,4'-dihydroxybenzophenone,4,4'-dihydroxyphenyl sulfone, 2,2bis(4-hydroxyphenyl)propane,2,2-bis(4-hydroxyphenyl)hexafluoropropane,1,1-bis(4-hydroxyphenyl)-1-phenyl ethane,9,9-bis(4-hydroxyphenyl)fluorene, 1,1-bis(4-hydroxyphenyl)cyclohexane,phenolphthalein, 3,3-bis(4-hydroxyphenyl)phthalimidine,N-phenyl-3,3-bis(4-hydroxyphenyl)phthalimidine, anddihydroxynaphthalenes (2,3- , 2,6- , 2,7-1,5- , 1,6- , 1,7- ).

The synthesis of diimide dicarboxylic acid (II) comprises heating anddehydrating ether chain-containing aromatic diamines and TMA at a molarratio of 1:2 in an appropriate solvent to polycondense. Suitablesolvents includes DMF, DMAc, NMP, DMSO, and sulfolane. The reactionscheme of this synthesis is illustrated as below: ##STR3##

In the polycondensation of the poly(amide-ehter-imide) of the presentinvention from diimide dicarboxylic acid(II) and aromatic diamine,triphenyl phosphite/pyridine are used as condensing agents. Suitablearomatic diamines have the formula of H₂ N--R₂ --NH₂, wherein R₂represents ##STR4## (Wherein R₁ represents the bisphenol components asformula III) ##STR5## In other words, the diamines include thefollowing: p-phenylenediamine, m-phenylenediamine, 2,4-toluenediamine,4,4'-biphenylenediamine, 3,3'-dimethyl-4,4'-diaminobiphenyl,4,4'-methylene dianiline, 4,4'-diaminobenzophenone, 4,4'-oxydianiline,3,4'-oxydianiline, 4,4'-diaminodiphenyl sulfide, 4,4'-diaminodiphenylsulfone, 3,3'-diaminodiphenyl sulfone, N-methylcarbozole-3,6-diamine,1,5-naphthalene diamine, 9,9-bis(4-aminophenyl)fluorene,2,5-bis(4-aminophenyl)-3,4-diphenylthiophene,1,4-bis(4-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene,1,2-bis(4-aminophenoxy)benzene, bis[4-(4-aminophenoxy)phenyl]ether,4,4-bis(4-aminophenoxy)biphenylene,2,4-bis[4-(4-aminophenoxy)phenyl]propane,2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane, and2,2-bis[4-(4-aminophenoxy)phenyl]sulfone.

The reaction scheme of this synthesis is illustrated as below:

This invention is more specifically described by the followingillustrative examples.

Preparative Example 1

To a 100 ml flask containing 1,4-bis(4-aminophenoxy)benzene (4.38 g) andTMA (5.76 g), anhydrous, purified DMF(30 ml) was added, stirred andallowed to react until a clear solution resulted. To this solution wasadded 10 ml of toluene. A Dean-Stark was connected to the flask, andheated in oil bath at 140° C. to remove the resulted water (about 0.55ml) by azeotropic distillation. After the reaction was completed, thetoluene was removed by distillation. After cooling, the precipitatedyellow solids were isolated by filtration and washed throughly withmethanol. The yield was 9.4 g (98%), m.p. 399° C.(DSC).

Elemental analysis data: calc. C: 67.50%, H: 3.15%, N: 4.37% found C:67.40%, H: 3.19%, N: 4.32%

The product, 1,4-bis(4-trimellitimidophenoxy)benzene, has the followingmolecular structure: ##STR7##

The following ether chain-containing diimide dicarboxylic acids wereprepared in a similar way. The yields were all above 90%.

    ______________________________________                                                                  m.p.(°C.)                                    ______________________________________                                        1,3-bis (4-trimellitimidophenoxy)benzene                                                                  350                                               2,5-bis (4-trimellitimidophenoxy)toluene                                                                  357                                               4,4-bis (4-trimellitimidophenoxy)biphenylene                                                              414                                               bis [4- (4-trimellitimidophenoxy)phenyl]ether                                                             351                                               bis [4- (4-trimellitimidophenoxy)phenyl]sulfide                                                           388                                               4,4-bis (4-trimellitimidophenoxy)benzophenone                                                             376                                               bis [4- (4-trimellitimidophenoxy)phenyl]sulfone                                                           323                                               2,2-bis [4-(4-trimellitimidophenoxy)phenyl]propane                                                        329                                               2,2-bis [4-(4-trimellitimidophenoxy)phenyl]-                                                              338                                               hexafluoropropane                                                             1,1-bis [4-(4-trimellitimidophenoxy)phenyl]-                                                              299                                               1-phenylethane                                                                9,9-bis [4-(4-trimellitimidophenoxy)phenyl]fluorene                                                       374                                               1,1-bis [4-(4-trimellitimidophenoxy)phenyl]cyclohexane                                                    309                                               3,3-bis [4-(4-trimellitimidophenoxy)phenyl]phthalide                                                      279                                               3,3-bis [4-(4-trimellitimidophenoxy)phenyl]phthalimidine                                                  210                                               N-phenyl,3,3-bis [4-(4-trimellitimidophenoxy)phenyl]-                                                     334                                               phthalimidine                                                                 ______________________________________                                    

Preparative Example 2

To a 100 ml flask containing 1,7-bis(4-aminophenoxy) naphthalene (3.4 g)and TMA (4.1 g), anhydrous, purified DMF(15 ml) was added, stirred andallowed to react until a clear solution resulted. To this solution wasadded 10 ml toluene. A Dean-Stark was connected to the flask, and heatedin oil bath at 140° C. to remove the resultant water (about 0.36 ml) byazeotropic distillation. After the reaction was completed, the toluenewas removed by distillation. After cooling, the precipitated yellowsolids were isolated by filtration and washed throughly with methanol.The yield was 6.48 g (94%), m.p.>400° C.(DSC).

Elemental analysis data: calc. C: 69.56%, H: 3.21%, N: 4.06% found C:69.39%, H: 3.38%, N: 4.05%

The product, 1,7-bis(4-trimellitimidophenoxy)naphthlene has thefollowing molecular structure: ##STR8##

The following ether chain-containing diimide dicarboxylic acids wereprepared in a similiar way:

    ______________________________________                                                              m.p.(°C.)                                                                     yield                                            ______________________________________                                        2,3-bis(4-trimellitimidophenoxy)naphthalene                                                           340      85%                                          2,6-bis(4-trimellitimidophenoxy)naphthalene                                                           402      98%                                          2,7-bis(4-trimellitimidophenoxy)naphthalene                                                           366      97%                                          1,5-bis(4-trimellitimidophenoxy)naphthalene                                                           436      99%                                          1,6-bis(4-trimellitimidophenoxy)naphthalene                                                           >440     95%                                          ______________________________________                                    

Preparative Example 3

To a 300 ml flask containing 1,2-bis(4-aminophenoxy)benzene (8.76 g) andTMA (11.7 g), anhydrouse DMF(40 ml) was added, and stirred at 40° C.until dissolution. To this solution was added 20 ml anhydrous toluene,boiled and stirred by azeotropic distillation for hours to remove water.The toluene was removed by distillation, cooled to room temperature, anda suitable amount of methanol was added until the precipitation ofyellow solids. The precipitated yellow solids were placed overnight,filtered, washed throughly with methanol, and dried. The product was ayellow powder of 18.86 g yield (99%), m.p. 320° C.(DSC).

Elemental analysis data: calc. C: 67.48%, H: 3.25%, N: 4.37% found C:67.68%, H: 3.24%, N: 4.43%

The product, 1,2-bis(4-trimellitimidophenoxy)benzene has the followingmolecular structure: ##STR9##

Example 1

In a 50 ml flask, was placed 4,4'-bis (4-trimellitimidophenoxy)benzene(0.801 g; 1.25 mmol), 2,2-bis [4-(4-aminophenoxy)phenyl]sulfone (0.540g; 1.25 mmol), N-methyl-2-pyrrolidone (NMP, 8 ml), calcium chloride (0.8g), pyridine (1.6 ml), and a condensing agent, triphenyl phosphite (0.8ml), which were stirred and allowed to react in a 100° C. oil bath for 3hours. A viscous solution resulted. The viscous solution was then pouredinto a stirred methanol. The product was a silk-like polymer of 1.319 gyield (100%), with an inherent viscosity of η_(inh) of 1.10 dl/g (0.5g/dl DMAc, 30° C.). Other properties of the product were measured anddescribed as below.

Elemental analysis data: (C₆₀ H₃₆ N₄ O₁₂ S.H₂ O)_(n) calc. C: 68.30%, H:3.63%, N: 5.31% found C: 68.19%, H: 3.96%, N: 4.98%

Mechanical strength:

tensile strength at break=62 MPa

elongation at break=9%

initial modulus=1.5 GPa

10% thermal weight loss temperature:

525° C. in air, 521° C. in N₂

Molecular structure: ##STR10##

Example 2

To a 50 ml flask, 2, 5-bis(4-trimellitimidophenoxy)toluene (0.818 g;1.25 mmol), 2,2-bis[4-(4-aminophenoxy)phenyl]ether (0.481 g; 1.25 mmol),NMP (8 ml), calcium chloride (0.7 g), pyridine (1.5 ml), and acondensing agent of triphenyl phosphite (0.8 ml) were added, which werestirred in a 100° C. oil bath for three hours, the other procedures wererepeated as in Example 1. A quantitative yield amount ofpoly(amide-imide) was obtained, which has an inherent viscosity η_(inh)of 1.26 dl/g in DMAc. Other properties of the product are described asfollows:

Elemental analysis data: (C₆₁ H₃₈ N₄ O₁₁.H₂ O )_(n) calc. C: 71.75%, H:3.95%, N: 5.48% found C: 71.09%, H: 4.16%, N: 5.46%

Mechanical strength:

tensile strength at break=76 MPa

elongation at break=10%

initial modulus=1.70 GPa

10% thermal weight loss temperature:

512° C. in air, 519° C. in N₂

Molecular structure: ##STR11##

Example 3

The same procedures as in Example 2 were repeatd, except that 2,2-bis[4-(4-aminophenoxy)phenyl]ether was replaced with m-phenylene diamine.The inherent viscosity η_(inh) thereof was measured as 1.58 dl/g inDMAc. Other properties of the product are described as follows:

Mechanical strength:

strength at yield point=85 MPa

tensile strength at break=78 MPa

elongation at break=19%

initial modulus=1.69 GPa

10% thermal weight loss temperature:

477° C. in air, 520° C. in N₂

Molecular structure: ##STR12##

Example 4

To a 50 ml flask, bis[4- (4-trimellitimidophenoxy)phenyl]ether (0.916 g;1.25 mmol), 2,5-bis[4-(4-aminophenyl)-3,4-diphenyl]thiophene (0.523 g;1.25 mmol), NMP(8 ml), calcium chloride (0.76 g), pyridine (1.6 ml), andcondensing agent of triphenyl phosphite (0.8 ml) were added, and stirredin a 100° C. oil bath for 3 hours, according to the same procedures asin Example 1. The resultant product had an inherent viscosity η_(inh) of1.46 dl/g in DMAc. Other properties of the product are described asfollows:

Mechanical strength:

tensile strength at break=97 MPa

elongation at break=39%

initial modulus=2.36 GPa

10% thermal weight loss temperature:

489° C. in air, 565° C. in N₂

Molecular structure: ##STR13##

Example 5

To a 50 ml flask, 1.25 mmol ofbis[4-(4-trimellitimidophenoxy)phenyl]sulfone, 1.25 mmol of4,4'-oxydianiline, anhydrous calcium chloride (0.76 g), NMP (8 ml),pyridine (1.6 ml), and condensing agent of triphenyl phosphite (0.8 ml)were added, stirred and allowed to react in a 100° C. oil bath for 3hours, according to the same procedures as described in Example 1. Theresultant poly(amide-imide) had a η_(inh) of 0.81 dl/g(DMAc). Otherproperties are described as follows:

Mechanical strength:

strength at yield point=81 MPa

tensile strength at break=79 MPa

elongation at break=19%

initial modulus=2.14 GPa

Molecular structure: ##STR14##

Example 6

To a reaction flask, 0.948g (1.25 mmol) of2,2-bis[4-(4-trimellitimidophenoxy)phenyl]propane, 0.513 g (1.25 mmol)of 2,2-bis[4-(4-aminophenoxy)phenyl]propane, anhydrous calcium chloride(0.8 g), NMP (8 ml), pyridine (1.5 ml), and triphenyl phosphite (0.8 ml)were added, stirred, and allowed to react at 100° C. for 3 hours,according to the same procedures as described in Example 1. Aquantitative yield of polymer was produced, which had a η_(inh) of 1.24dl/g(DMAc). Other properties are described as follows.

Elemental analysis data: (C₇₂ H₅₂ N₄ O₁₀.1.5H₂ O)_(n) calc. C:74.53%,H:4.78%, N:4.83% found C:74.78%, H:4.36%, N:4.88%

Mechanical strength:

strength at yield point=85 MPa

tensile strength at break=88 MPa

elongation at break=53%

initial modulus=2.34 GPa

10% thermal weight loss temperature:

478° C. in air, 519° C. in N₂

Molecular structure: ##STR15##

Example 7

To a reaction flask 1.083 g (1.25 mmol) of2,2-bis[4(4-trimellitimidophenoxy)phenyl]hexafluoropropane, 0.720 g(1.25 mmol) of N-phenyl-3,3-bis[4-(4-aminophenoxy)phenyl]phthalimidine,calcium chloride (0.8 g), NMP (8 ml), pyridine (1.6 ml), and triphenylphosphite (0.8 ml) were added, stirred, and allowed to react at 100° C.for 3 hours, according to the same procedures as described in Example 1.A polymer was produced, which had a η_(inh) of 0.72 dl/g(DMAc). Otherproperties are described as follows:

Mechanical strength:

strength at yield point=82 MPa

tensile strength at break=77 MPa

elongation at break=13%

initial modulus=2.28 GPa

10% thermal weight loss temperature:

501° C. in air, 540° C. in N₂

Molecular structure: ##STR16##

Example 8

To a 50ml reaction flask 1.026 g (1.25 mmol) of1,1-bis[4-(4-trimellitimidophenoxy)phenyl]-1-phenylethane, 0.365 g (1.25mmol) of 1,3-bis(4-aminophenoxy)benzene, calcium chloride (0.6 g), NMP(6 ml), pyridine (1.2 ml), and triphenyl phosphite (0.8 ml) were added,stirred and allowed to react at 100° C. for 3 hours, according to thesame procedures as described in Example 1. A polymer was produced, whichhad a η_(inh) of 1.07 dl/g(DMAc). Other properties are described asfollows:

Elemental analysis data: (C₆₈ H₄₄ N₄ O₁₀.2H₂ O)_(n) calc. C:73.40%,H:4.56%, N:5.04% found C:73.50%, H:4.34%, N:4.98%

Mechanical strength:

strength at yield point=79 Mpa

tensile strength at break=83 Mpa

elongation at break=9%

initial modulus=1.78 Gpa

10% thermal weight loss temperature:

508° C. in air, 528° C. in N₂

Molecular structure: ##STR17##

Example 9

To a 50 ml flask 2.5 mmol ofN-phenyl-3,3-bis[4-(4-trimellitimidophenoxy)phenyl]phthalimidine, 2.5mmol of 4,4'-oxydianiline, anhydrous calcium chloride (0.6 g), NMP (6ml, and extra 5.5 ml was added thereafter, because the difficulties ofstirring due to high viscosity), pyridine (1.4 ml), and condensing agentof triphenyl phosphite (0.8 ml) were added, stirred and allowed to reactfor 3 hours, according to the same procedures as described in Example 1.A polymer was produced with a η_(inh) of 0.87 dl/g(DMAc). Otherproperties are described as follows:

Mechanical strength:

tensile strength at break=89 MPa

elongation at break=9%

initial modulus=2.38 GPa

Molecular structure: ##STR18##

Example 10

To a 50 ml reaction flask, 2,7-bis(4-trimellitimidophenoxy)naphthalene(0.86 g; 1.25 mmol), m-phenylenediamine (0.135 g; 1.25 mmol), NMP (8ml), calcium chloride (0.8 g), pyridine (1.6 ml), and a condensing agentof triphenyl phosphite (0.8 ml) were added, and allowed to react in a100° C. for 3 hours. The resultant viscous solution was then poured intoa stirred methanol to provide a stringy polymer precipitate. Afterwashing with methanol and hot water throughly, the polymer was dried toyield 0.953 g product(100%). The product had an inherent viscosity ofη_(inh) of 1.57 dl/g (0.5 g/dl DMAc, 30° C.). Other properties aredescribed as follows:

Elemental analysis data: (C₆₇ H₄₄ N₄ O₁₀.H₂ O)_(n) calc C: 69 10% H: 375%, N: 7 01% found C: 69 39% H: 3 69%, N: 7 03%

Mechanical strength:

tensile strength at break=74 MPa

elongation at break=9%

initial modulus=1.5 GPa

10% thermal weight loss temperature:

506° C. in air, 565° C. in N₂

Molecular structure: ##STR19##

Example 11

To a 100 ml reaction flask, 0.8 g (1.25 mmol) of1,2bis(4-trimellitimidophenoxy)benzene, 0.25 g (1.25 mmol) of4,4'-oxydianiline, anhydrous calcium chloride (0.7 g), NMP (8 ml),pyridine (1.4 ml), and triphenyl phosphite (0.8 ml) were added, stirredand allowed to react in a 100° C. oil bath under a nitrogen atmospherefor 3 hours. The resultant viscous solution was slowly poured to astirred methanol to yield a stringy polymer precipitate. After beingsoaked in methanol and warm water for 4 hours respectively, theresultant polymers was dried to yield 1.00 g polymer(100%). The pollymerhad an inherent viscosity of 1.34 dl/g(DMAc-1% LiCl). A tough film ofthe product could be cast from NMP. Other properties are described asfollows:

Mechanical strength:

strength at yield point=97 MPa

tensile strength at break=89 MPa

elongation at break=11%

initial modulus=2.37 GPa

Molecular structure: ##STR20##

Example 12

The same procedures as described in Example 11 were repeated, exceptthat 4,4'-oxydianiline was replaced with 4,4'-diaminodiphenyl sulfide.The resultant product had an inherent viscosity of 1.2 dl/g. Themechanical properties of the film cast from DMAc were:

strength at yield point=76 MPa

tensile strength at break=67 MPa

elongation at break=11%

initial modulus=2.63 GPa.

Molecular structure: ##STR21##

Example 13

A diimide dicarboxylic acid was prepared by condensing2,2-bis[4-(4-aminophenoxyl)phenyl]propone (1.0 mol) and TMA (2.0 mol) inDMF according to the procedures as described in preparative Example 1.1.25 mmole of the resultant diimide dicarboxylic acid and1,2-bis(4-aminophenoxy)benzene (1.25 mmol) were added to a 100 mlreaction flask. Solvents and a condensing agent, including anhydrouscalcium (0.7 g), NMP (8 ml), pyridine (1.2 ml), and triphenyl phosphite(0.8 ml) were then added, stirred and allowed to react in a 100° C.glycerol bath for 3 hours(an extra 3 ml of NMP was added when theviscosity increased after 1 hour of reaction). After the completion ofthe reaction, the resultant viscous solution was poured to a stirredmethanol solution to yield a stringy polymer precipitate (100%). Thesolid had an inherent viscosity of 1.9 dl/g (DMAc-5%LiCl, 30° C.). Themechannical porperties of the film cast from DMAc were:

Mechanical strength:

strength at yield point=83 MPa

tensile strength at break=72 MPa

elongation at break=17%

initial modulus=2.28 GPa

Molecular structure: ##STR22##

What is claimed is:
 1. A poly(amide-ether-imide of the formula:whereinR₁ is selected from the group consisting of: ##STR23## and R₂ isselected from the group consisting of: ##STR24## wherein R is anhydrogen atom or CH₃ -- and R₁ is defined above.
 2. Apoly(amide-ether-imide) as claimed in claim 1, wherein R₁ is ##STR25##and R₂ is ##STR26##
 3. A poly(amide-ether-imide) as claimed in claim 1,wherein R₁ is ##STR27## and R₂ is ##STR28##
 4. A poly(amide-ether-imide)as claimed in claim 1, wherein R₁ is ##STR29## and R₂ is ##STR30##
 5. Apoly(amide-ether-imide) as claimed in claim 1, wherein R₁ is ##STR31##and R₂ is ##STR32##
 6. A poly(amide-ether-imide) as claimed in claim 1,wherein R₁ is ##STR33## and R₂ is ##STR34##
 7. A Poly(amide-ether-imide)as claimed in claim 1, wherein R₁ is ##STR35## and R₂ is ##STR36##
 8. APoly(amide-ether-imide) as claimed in claim 1, wherein R₁ is ##STR37##and R₂ is ##STR38##
 9. A poly(amide-ether-imide) as claimed in claim 1,wherein R₁ is ##STR39## and R₂ is ##STR40##
 10. Apoly(amide-ether-imide) as claimed in claim 1, wherein R¹ is ##STR41##and R₂ is ##STR42##
 11. A poly(amide-ether-imide) as claimed in claim 1,wherein R₁ is ##STR43## and R₂ is ##STR44##
 12. Apoly(amide-ether-imide) as claimed in claim 1, wherein R₁ is ##STR45##and R₂ is ##STR46##
 13. A poly(amide-ether-imide) as claimed in claim 1,wherein R₁ is ##STR47## and R₂ is ##STR48##
 14. A poly(amide-ether-imide) as claimed in claim 1, wherein R₁ is ##STR49## andR₂ is ##STR50##
 15. A poly(amide-ether-imide) as claimed in claim 1,wherein R₁ is ##STR51## and R² is ##STR52##
 16. A method of preparingthe poly(amide-ether-imide) (I) as described in claim 1, wherein saidmethod comprising the steps of:a) conducting a thermal condensationreaction by reacting an ether chain-containing aromatic diaminerepresented by formula III with trimellitic anhydride to form a diimidedicarboxylic acid represented by formula II in a polar solvent, whereinR₁ is defined as in claim 1; formula II is represented by the followingformula: ##STR53## and formula III is represented by the followingformula: ##STR54## b) conducting a polycondensing reaction by reactingsaid diimide dicarboxytic acid represented by formula II and an aromaticdiamine of the formula H₂ N--R₂ --NH₂ to form saidpoly(amide-ether-imide), wherein R₂ is defined as in claim 1.